package com.aaa.gateway.filter;


import com.alibaba.fastjson.JSON;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Map;

/**
 * @author ：ludi（206913808@qq.com）
 * @date ：Created in 2022/11/22 15:09
 * @description：
 * @modified By：
 * @version:
 */
@Component
public class LoginFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();
        String path = request.getPath().toString();
        if("/login".equals(path)){
            return chain.filter(exchange);
        }
        String token = request.getHeaders().getFirst("token");
        if (StringUtils.hasText(token)){
            if ("admin".equals(token)){
                return chain.filter(exchange);
            }
        }
        //设置状态码
        response.setStatusCode(HttpStatus.UNAUTHORIZED);
        //封装返回数据
        Map<String, Object> map = new HashMap<>();
        map.put("msg", "未登录");
        map.put("code", "NOTLOGING");
        //JSON转换
        byte[] bytes = JSON.toJSONString(map).getBytes(StandardCharsets.UTF_8);
        //调用bufferFactory方法,生成DataBuffer对象
        DataBuffer buffer = response.bufferFactory().wrap(bytes);
        //调用Mono中的just方法,返回要写给前端的JSON数据
        return response.writeWith(Mono.just(buffer));
    }

    /**
     * 优先级--值越小,优先级越高
     */
    @Override
    public int getOrder() {
        return 0;
    }
}